The concurrent expression of p27(kip1) and cyclin D1 in epithelial ovariantumors

Mammalian cell-cycle progression is regulated by the combined action of cyc lins/cyclin-dependent kinases (cdks) and cdk inhibitors. Abnormal expressio n as well as interaction of these proteins may result in malignant transfor mation of cells, To further address alterations and roles of these cell-cyc le proteins in the development of epithelial ovarian carcinomas, we analyze d the expression of the p27(kip1), cyclin D1, cyclin E, and cdk2, A panel o f 79 epithelial ovarian tumors was selected. Immunohistochemical staining o f serial paraffin sections was performed using antibodies to p27(kip1), cyc lin D1, cyclin E, and cdk2, The results showed that p27(kip1) and cyclin D1 were concurrently expressed in epithelial ovarian tumors, and the expressi on was down-regulated in ovarian carcinomas. There was an inverse relations hip between the expression level of p27(kip1) and cyclin D1 and the histolo gical tumor grades. On the other hand, the expression of cyclin E and cdk2 was enhanced in ovarian carcinomas. The results suggest that low expression of p27(kip1) and cyclin D1 as well as high expression of cyclin E and cdk2 promotes the development of ovarian tumors. p27(kip1) and cyclin D1 expres sion are negatively correlated with the malignant degree of epithelial ovar ian tumors. Thus, the ovarian tumors with high p27(kip1) and cyclin D1 expr ession may generally have a somewhat better prognosis, while those with low p27(kip1) and cyclin D1 expression may have a worse prognosis. (C) 1999 Ac ademic Press.